Refractive Consequences of Epiretinal Membrane Surgery (EPIREF)

Epiretinal membrane is treated with vitrectomy and peeling. Afterwards cataract is usually developed, which requires a cataract surgery.

The aim of this study is to investigate the refractive consequences of surgery for Epiretinal membrane and cataract.

Investigators investigate the sequence of surgery in patients having surgery for Epiretinal membrane and cataract in a prospective clinically randomized intervention trial. Patients are randomized to 1) start with vitrectomy, 2) start with cataract surgery, 3) combined surgery. Investigators want to find the sequence of surgery that gives the most optimal refractive result, the most stabile intraocular lens, and the minimal loss of corneal endothelial cells.

Study Overview

• Status: Completed
• Conditions: Epiretinal Membrane
• Intervention / Treatment: Procedure: Cataract surgery; Procedure: Vitrectomy; Procedure: Combined surgery

Detailed Description

Aim: To evaluate the impact of the sequence of surgery on the Refractive Error and the Corneal Endothelial Count in phakic individuals undergoing surgery for Epiretinal membrane.

Study design: Prospective interventional randomized clinical trial. Primary outcome: Refractive error (i.e. Intraocular lens power prediction error), Corneal Endothelial Count, and postoperative macular oedema.

Secondary outcome: Changes in axial length, anterior chamber depth and keratometry; the accuracy of formulas used to calculate the power of the intraocular lens.

Study population:

Identification of participants: Individuals referred to the Macular Surgery Clinic, Surgical Retina Team, Department of Ophthalmology, Glostrup University Hospital, Copenhagen, Denmark. The individuals should be signed up for surgery because of Epiretinal membrane at the clinic.

Method:

Individuals are randomized to the possible sequences of surgery (i.e. start with cataract surgery, start with vitrectomy, or combined surgery). Based on an estimated clinical relevant refractive prediction error of 0,50 diopter and a standard deviation of 0,50 diopter, a number of 20 individuals in each of the three groups are needed to obtain a power of 80 % and a type 1 error of 5 %. Total number of individuals is thus 60.

Clinical examinations are performed preoperatively and 2 weeks after each surgery (cataract surgery, vitrectomy or combined surgery), and 3 and 12 months postoperatively. The examinations include best corrected distance visual acuity, autorefraction/keratometry (Retinomax®, Nikon, Tokyo, Japan), subjective refraction, slit-lamp examination, fundoscopy and tonometry. Biometry by IOLMaster (Carl Zeiss, Meditec AG, Germany), intraocular power calculation with the SRK/T formula. Pentacam Scheimpflug Cornea tomography (Topcon, Tokyo, Japan). Corneal Endothelial Count obtained by three images of the central region of the corneal endothelium (Topcon SP-3000P, Tokyo, Japan). Heidelberg Optical Coherence Tomography, (Heidelberg Engineering, Heidelberg, Germany).

Sequence of surgery depends on randomization. In all cases a standard phacoemulsification (scleral tunnel or clear corneal incision) with in-the-bag intraocular lens implantation. In combined surgery, the cataract surgery is performed before vitrectomy during the same session. Vitreoretinal procedures include a standard three-port 23 gauge pars plana vitrectomy, membrane peeling, and the use of dyes. Cataract surgery is performed by one of two experienced surgeons, and vitrectomy is carried out by one experienced surgeon.

Analysis: A computer database will be created as a fill-in form to record all patient data, and a masked statistical analysis of all outcome measures will be performed. Statistical analysis will be performed to determine differences in baseline data among the three groups (age, sex, visual acuity, keratometry, axial length, anterior chamber depth, Corneal Endothelial Count). To identify independent predictors for all outcome measures at different follow-up times, multivariate regression analysis is performed. All calculations will be performed using SAS software.

• Study Type: Interventional
• Enrollment (Actual): 62
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Denmark
  • DK
    • Glostrup, DK, Denmark, 2600
      • Eye Department Glostrup Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 50 years to 99 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion criteria:

• A diagnosis of Epiretinal membrane,
• visual complaints consistent with Epiretinal membrane,
• age more than 50 years,
• refraction less than ± 5 diopters and astigmatism less than 3 diopters,
• indication for vitrectomy is only Epiretinal membrane.

Exclusion criteria:

• Previous intraocular surgery or laser-refractive procedure.
• Use of intraocular gas tamponade during the vitrectomy.
• Intraoperative manipulation of the intraocular lens.
• Serious complications (endophthalmitis, vitreous haemorrhage or retinal detachment).
• History of previous head or ocular trauma.
• Sulcus fixation of intraocular lens

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Non-Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Start cataract; Patients start having cataract surgery. After one month they undergo vitrectomy	Procedure: Cataract surgery; Cataract surgery
Active Comparator: start vitrectomy; Patients start having vitrectomy. After one month they undergo cataract surgery.	Procedure: Vitrectomy; Vitrectomy
Active Comparator: combined surgery; Combined cataract surgery and vitrectomy at the same time	Procedure: Combined surgery; Combined vitrectomy and cataract surgery at the same time

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Refractive Error	Prediction error of intraocular lens calculation (measured in diopters)	One year
Corneal endothelial count	measured in number of cells per square millimeter (mm2)	One year
Macula anatomy	Macula-anatomy success of surgery, i.e. the postoperative decrease of macula thickness or postoperative macular oedema. Measured in millimeter.	One year

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Anterior Chamber Depth	measured in millimeter (mm)	One year
Axial length	measured in millimeter (mm)	One year

Collaborators and Investigators

• Sponsor: Glostrup University Hospital, Copenhagen
• Investigators: Principal Investigator: Hassan Hamoudi, MD, Eye Department Glostrup Hospital

Study record dates

Study Major Dates

• Study Start: May 1, 2014
• Primary Completion (Actual): October 1, 2016
• Study Completion (Actual): October 1, 2016

Study Registration Dates

• First Submitted: March 27, 2015
• First Submitted That Met QC Criteria: April 7, 2015
• First Posted (Estimate): April 10, 2015

Study Record Updates

• Last Update Posted (Estimate): November 10, 2016
• Last Update Submitted That Met QC Criteria: November 9, 2016
• Last Verified: November 1, 2016

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Eye Diseases; Retinal Diseases; Epiretinal Membrane
• Other Study ID Numbers: EPIREF